Actuator valve system for two-stage fluid-operated unit



United States Patent Inventor Theodore J. Roy! Columbus, Ohio App]. No. 810,246 Filed Mar. 25, 1969 Patented Dec. 22, 1970 Assignee The Jaeger Machine Company Columbus, Ohio a corporation of Ohio ACTUATOR VALVE SYSTEM FOR TWO-STAGE FLUID-OPERATED UNIT 5 Claims, 5 Drawing Figs. 11.8. 91/307, 91/313, 91/329, 91/341 Int. F01] 25/06, F011 23/00 Field ofSeareh 91/307,

313, 329, 341(Cursory) [56] References Cited UNITED STATES PATENTS 2,642,045 6/1953 Potts 91/313 2,896,903 7/1959 Canalizo... 91/307 3,261,265 7/1966 Weik 91/313 Primary ExaminerPaul E. Maslousky Attorney-Mahoney, Miller & Stebens ABSTRACT: An actuator valve system for a two-stage fluidoperated unit in which a main pilot-operated valve controls the supply and exhaust of fluid to the unit and the positioning of the valve is controlled by a pilot control sleeve which is operatively connected to the valve to apply actuating fluid pressure thereto and, in turn, is positively axially moved to its different positions mechanically by movement of the fluid-actuated unit with which it is cooperatively positioned.

PATENTED 052221970 SHEETIUFB a v1 l i Q g INVENTOR. THEODORE J. RAYL ATTORNEYS PATENTED DEE22|97U 35 sum 2 OF 3 INVENTOR. THEODORE J. RAYL BY Mgfv-iONEY, MILLER 8 RAMBO TTORNEYS ACTUATOR VALVE SYSTEM FOR TWO-ST AGE FLUID- OPERATED UNIT devices. The present invention provides a system which can employ a standard pilot-operated four-way valve as the main valve and a simple pilot control sleeve to supply pilot fluid to the control valve, the sleeve being positioned so that it is positively moved axially by the pistons or diaphragms of the pump actually contacting therewith as they complete their respective strokes.

In the accompanying drawings, I have illustrated a preferred embodiment of my invention and in these drawings:

FIG. I is an axial sectional view through a pump unit of the diaphragm type to which the valve control system has been applied. 7

FIG. 2 is an enlarged axial sectional view showing the pilot control sleeve and its mounting and indicating how it is actuated.

FIG. 3 is an enlarged transverse sectional view taken along line 3-3 of FIG. 1 and showing the main control valve in one position.

FIG. 4 is a similar view but showing the valve in its other or reversing position as compared to FIG. 3.

FIG. 5 is a transverse sectional view taken along line 5-5 of FIG. 3.

With reference to the drawings, I have illustrated my invention applied to a two-stage opposed work device, more particularly, a two-stage air-operated diaphragm pump which is illustrated in FIG. 1. However, it is to be understood my invention is not limited to this specific type of pump, but is applicable to various two-stage opposed work devices. An actuator valve systemaccording to my invention is provided for actuating this pump and includesa pilot operated four-way actuator valve 10, which is controlled by an actuator unit 1 l. The valve controlled by the actuator 11 is designed to supply drive media, such as compressed air, to the pump in sucha manner as to actuate the pump to cause it to p'erform'a desired pumping operation. p

The pump is illustrated as comprising the disclike pistons 12 and 13 which are connected to the opposite ends of a reciprocable shaft or rod 14. The pistons 12 and 13 are movably mounted in the pump housing by the respective diaphragms l5 and 16, which are clamped between separate sections of the pump housing. The housing sections of the pump are such that the piston 12 has the main pump chamber 17 at one side thereof and an actuating chamber 18 at the other side thereof. Similarly, the piston 13 has a main pump chamber 19 at one side thereof and an actuating chamber 20 at the other side thereof. As will be explained later, pressure is alternately supplied to and exhausted from the chambers 18 and 20 to move the pistons 12 and 13in the same direction and to simultaneously reciprocate the shaft 14. The chamber 17 has an inlet 21 and a discharge outlet 22 and similarly, the chamber 19 has an inlet 23 and a discharge outlet 24. Movement of the pistons 12 and 13 will draw the fluid to be pumped successively through the inlets 21 and 23 and discharge it through the outlets 22 and 24. The actuating media or the drive media for the pump, as indicated above, will be described as compressed air, but thedevice is not limited to the use of compressed air since other gases or fluids can be used as the drive media. Furthermore, as also indicated above, the particular pump is given by way of example only since my invention is applicable to other types of work devices.

The pump housing includes the inner heads 25 and 26 between which is fixed the actuator housing 27 of the actuator unit 11 which is of hollow form and which has an axially extending adapter 28 formed integral therewith and interiorly thereof. This adapter 28 serves as a bearing for the shaft 14. A valve control sleeve 29 is slideably disposed within the adapter 28 and around the shaft 14 on which it can slide. The shaft, sleeve, and adapter are concentric and are axially aligned with pistons 12 and 13 and the shaft can reciprocate axially relative to the adapter. A main exhaust passage leads radially from the actuator housing 27 and is provided with, an exhaust fitting 30.

It will be noted that the sleeve 29 is of an axial extent substantially less than that of the axial spacing-of the pistons 12 and 13, but greater than the spacing of the heads'25 and 26, so that the sleeve will always project into one or both of the actuating chambers 18 and 20.

The sleeve 29 has axially spaced circumferential grooves 31 and 32 formed therein which are connected respectively to the axially spaced exhaust openings 33 and 34 in the adapter 28. Also located in the adapter 28 are the spaced pilot-exhaust passages 35 and 36. The sleeve 29 is slideable on the shaft 14 and the opposite projecting ends of the sleeve will be engaged by the respective pistons 12 and 13 as they approach the respective heads 25 and 26.

The main valve 10 is mounted on a flattened side 37 of the actuator housing 27 as shown in FIG. 3. This valve may be any standard four way pilot-operated valve which is not biased in any particular position. It is designed to supply drive media to space 20 behind the piston 13 and simultaneously exhaust space 18 behind the piston 12 to move the pistons 12 and 13 and connecting shaft 14 to the right as viewed in FIG. 1. At a predetermined extent of travel or stroke, the procedure is reversed by contact of the piston 12 with the end of the adapter sleeve 29, which at that time will be projecting into the space 18, and drive media is then supplied to the space 18, while the space 20 is exhausted. This moves the pistons 12 and 13 and the connecting shaft 14 to the left,

The main valve 10 illustrated is of the spool type and comprises a housing 40 having a valve sleeve 41 fixed in a bore extending completely therethrough with a valve spool 42 slideably mounted in the sleeve. A connection 43 is provided for receiving an actuating fluid, in the form of compressed air from a suitable source of supply and for supplying it in to a passage 44 in the valve housing leading to opposite ends thereof and connecting to an orifice 45 at one end and an orifice 46 at the other end which lead into the opposite ends of the valve sleeve 41. g

The housing 40 is provided with five passages, 51, 52, 53, 54, and 55, which are connected to the, interior of the valve sleeve 41 at axially spaced intervals. The fluid supply passage 44 connects intermediate its end with the passage 51 which surrounds the valve sleeve 56. With the valve spool 42 in the position shown in FIG. 3, the pressure passage 51 is connected to the passage 53, the passage 52 is connected to the exhaust passage 55, and the passage 54 is closed. When the spool 42 is in its opposite position as shown in FIG. 4, the pressure passage is connected to the passage 52, the passage 53 is connected to the exhaust passage 54 and the passage 55 is closed.

It will be noted that passages 54 and 55 are exhaust passages which align with passages 50 and 59 respectively, that open into the interior of the actuator housing 27 and, therefore, connect with the exhaust 30. The passage 52 leads to a passage 57 in the adapter 28 which, in turn, leads axially of the adapter into the chamber 18 behind the piston -13.

When compressed air is introduced at the connection 43 and the spool 42 is in the position shown in FIG. 3, it will flow through passages 51, 53 and 58 into the chamber 20 while the chamber 18 will be connected to the exhaust 30 through the passages 57, 52, 55, and 59. This will produce movement of the pistons 12 and 13 to the right as viewed in FIG. 1. When the spool 42 is in the opposite position shown in FIG. 4, the compressed air will flow into the chamber 18 through the passages 51, 52, and 57 and the air in the chamber 20 will be exhausted through the passages 58, 53, 54, and 50 and finally outlet 30. This will result in movement of the pistons 12 and 13 in the opposite direction or to the left of FIG. 1.

Compressed air is continually supplied through the orifice 45 to the space 60 at the one end of the valve housing and passes intothe sleeve 41 at that end. It is also continually supplied through the orifice 46 into a space 61 communicating with the other end of the valve sleeve 41. The space 61 is connectedby a passage 62 to the passage 35 in the adapter 28. Similarly, the space 60.is connected by a passage 63 to the passage 36 in the adapter 28. If passage 62 is closed while passage 63is open to exhaust, air pressure will build up in the chamber 61 and be relieved or exhausted from the chamber 60 so as to hold thespool 42 in the position shown in FIG. 3.

On the other hand, if passage 63 is closed and the passage 62 is open to exhaust, air pressure will build up in the chamber 60 and be relieved from the chamber 61 so as to move the spool 42 to the position shown in FIG. 4. The passages 61 and 63, therefore, provide pilot control of the valve spool 42 and determine proper direction of movement for pistons 12 and 13.

The passages 62 and 63 are controlled in accordance with the control of passage35 and 36 with which they communicate and, as previously indicated, these passages are under the control of the valve control sleeve 29 which reciprocates in the adapter 28 in accordance with movement of the pistons 12 and 13 and the connected rod 14. The grooves 31 and 32 in the sleeve-29 are so positioned that when the sleeve 29 is moved as far as possible toward the piston 12, as shown in work unit, is positively controlled by mechanical contactof reciprocable parts of the unit with the control sleeve. The stroke of the unit can be varied by varying the length of the control sleeve. As pressurized drive media is continuously applied through metered orifices to both ends of the valve spool or piston, the spool willalways move to and stay in the desired location as determined by'the position of the pilot control sleeve. Also, slight leakage can be overcome by the continuous supply of pressure"media"' through the metered orifices. The continuous venting'of'on e'e'nd of the valve plus continuous application of pressure media to the opposite end insures proper function of the control valve during the work cycle. The pressure of drive media applied to the end of the pilot control sleeve insures complete shifting of the sleeve. As the end of the pilot control sleeve is always exposed to pressure drive media, irrespective of the position of the'c ontrol valve, the work unit will always start even under very small load conditions. Conventional sealing means can be used between the control sleeve and the shaft on which it is slideably mounted. The control sleeve structure is simple and inexpensive and makes it possible to use a standard four-way valve, which' posed actuating chambers cooperating therewith and adapted FIG. 1, with its right hand end flush with the inner surface of l the head 26, the passage in the adapter 35 is closed and the passage 36 in the adapter is connected to the exhaust through thegroove 32in the sleeve and the exhaust opening 34 in the adapter. This vents air from the space 60 at the one end of the spool42 and allows air pressure to build up in the space 61 at the other end of the spool to hold it in the position shown in FIG. 3.. In this position, the chamber 18 behind the piston 12 is opened to exhaust through the passages 57, 52, 55, 59,and 30 and air under pressure is supplied to chamber 20 through the passages 51, 53, and 58. This will move the pistons 12 and 13 and the connected shaft 14 to the right, as viewed in FIG. 1. Pressure of air in the space 20 will act on the end of the control sleeve 29 and will tend to hold the sleeve in the position indicated in FIG. 1, where it will be noted that the opposite end of the sleeve will be projecting into the chamber 18.

When the piston 12 nears the end of its desired travel to the right, it contacts the projecting end of the sleeve 29 and moves the sleevein the same direction of its movement. This positions the groove 32 of the sleeve away from the adapter groove 36 and, consequently, closes the groove 36 from exhaust which closes thespace 60 to exhaust and builds up pressure. therein at that endof the spool 42. Continued movement of the piston 12 and the sleeve 29 connects the adapter groove through the sleeve. groove 31 to the adapter outlet 33 and then on through the housing 27 to the exhaust 30. This will exhaust or vent the air from the space 61 at the other end of the spool 42. As air pressure hasalready built up in the space 60 at the end of the spool, it will be moved to the position shown in FIG. 4 and reverse the piston movement by connecting the chamber 20 to exhaust and the chamber 18 to the pressure supply so as to move the pistons 12 and 13 to the left of FIG. 1. Also, pressure of air in the chamber 18 acting on the end of the valve control sleeve 29, which will at that time be flush with the inner surface of head 25, will tend to hold the sleeve in its new position until the pistons reach their limit of travel and piston 13 contacts the sleeve 29 to move it to its original position shown in FIG. 1 so as to repeat the operation. Cushioning washers 65 may be provided on the ends of the sleeve 29 to reduce impact at times of contact with the respective pistons.

It will be apparent from the above description that I have provided an actuator valve system for a double-acting fluidoperated work unit which can use various commercially available pilot-operated four-way valves. The positioning of the four-way valve which, in turn, controls the stroke of the to alternately receive actuating pressure and have the pressure vented therefrom to reciprocate the cooperating work members, said work members being connected together for simultaneous movement by a shaft, an actuating valve system for alternately supplying actuating fluid pressure to one. of said chambers and exhausting it from the other, said valve system comprising a main four-way control valve having passages connected to said chambers and to exhaust and having a pilotcontrolled movable valve member for selectively connecting said passages to alternately supply actuating pressure to one of the said chambers while exhausting it'from the other, means for continuously supplying pilot pressure to said valve which can be controlled to move said valve member in opposite. directions, mechanical control means for controlling the pilot pressure to move said valve member as the reciprocable work members and connecting shaft near the end of their stroke in' either direction so as to reverse the stroke, said control means comprising a control sleeve surrounding said shaft and slidably' mounted thereon and having opposed ends which are exposed at said opposed actuating chambers, said sleeve being mounted for slidable movement in a surrounding adapter hav-. ing pilot fluid exhaust passages connected to said valve, said sleeve having passages which, upon reciprocation thereof, al-i ternately connect said pilot exhaust passages to vent openings in said adapter so as to move said valve member in accordancewith the movement of said work members to reverse move-: ment thereof.

2. The combination of claim 1 in which the work members are in opposed axial alignment and the connectingshaft is':

disposed therebetween in axial alignment, said adapter includ-i ing a bearing portion surrounding said sleeve and having the, pilot fluid exhaust passage form therein, said pilotfexhaust;

chamber has heads facing towards each other in axially spacedt relationship with the adapter disposed therebetween, a house ing surrounding said adapter and extending between said! heads and having an exhaust opening, saidtsleeve being oii greater axial extent than the adapter so that its ends will al-Z ways extend at least to the inner faces of the respective heads.

4. The combination of claim 3 in whichthe work elements"- are pistons which are fixed to said shaft and are adapted to engage the respective ends of the control sleeve carried on said shaft.

5. The combination of claim 4 in which the ends of the control sleeve are provided with cushioning elements to absorb impact upon contact with said pistons. 

